Abstract

The Sobradinho Reservoir is one of the most important in the northeast of Brazil, therefore, the perennial and adequate monitoring of this area reflects in good practices in the economy and quality of life. Thus, understanding the best altimetric database for the region is essential to initiate and assist in other monitoring processes, since the relevance of altimetric studies in several areas is observed. Therefore, this work aims to evaluate, through a comparative analysis, the SRTM models (30 and 90 meters) and ASTER (30 meters) for the Sobradinho Reservoir region. SRTM images (30 and 90 meters) and ASTER were acquired, where it was executed its mosaic and altimetric classification through the software ERDAS imagine 9.1. In the analysis, it is verified that the values of the digital elevation models ASTER do not agree with the academic literature for the region. The SRTM model of 90 meters resolution maintains values within the observed in the literature, however, in the water body of the reservoir occurs the error called sinks. The SRTM 30-meter resolution maintains the best data quality, error-free and according to the literature. Through this manuscript, it is recommended to use the SRTM digital elevation model of 30 meters resolution for the Sobradinho Reservoir region, due to the excellent results found.